Mouthpiece for hollow strand pressses for the production of closed hollow bricks from plastic materials



July 6, 1937. J. PUTTERLIK 2,036,285

MOUTHPIECE FOR HOLLOW STRAND PRESSES FOR THE PRODUCTION OF CLOSED HOLLOW BRICKS FROM PLASTIC MATERIALS Filed Dec. 2-5, 1935 Patented July 6, 1937 UNITED STATES MOUTHPIECE PRESSSES- FOR HOLLOW FOR THE PRODUCTION OF STRAND CLOSED HOLLOW BRICKS FROM PLASTIC MATERIALS Jan Putterlik, Prague,

Czechoslovakia, assignor to Aktiengesellschaft i'iir Industriegas-Verwertung, Berlin-Britz, Germany Application December 23, 1935, Serial No. 55,862 In Czechoslovakia October 25, 1934 1 Claim.

This invention relates to the manufacture of closed hollow bodies from plastic materials such for example as closed hollow bricks or building blocks of clay.

It is known to employ for this purpose an extrusion press having a mouthpiece from which the plastic material issues as a hollow strand closed or partitioned at intervals by interior plugs of the same material, the individual closed, hollow bodies being formed by severing the strand centrally through the plugs.

The known arrangements have not proved entirely satisfactory in use, mainly for the reason that the plastic material when issuing from the hollow core of the mouthpiece, which core forms the aforementioned interior plugs, could not be easily and accurately cut from the remaining with ribs. These ribs produce on the outer surface of the passing solid strand small channels through which constantly air can pass from the front of the mouthpiece to the severing place of the plug, that is to say to the outlet end of the hollow core.

Upon the accompanying drawing one suitable form of construction of the mouthpiece according to the invention is shown and itis:

Figure 1 a front view of the hollow core of the mouthpiece and V Figure 2 a longitudinal section of Figure l.

The hollow core I of the mouthpiece has double walls consisting of the actual wall of the hollow core and of an inner wall I formed by corrugated sheet iron. According to this construction the air is passed on the top and below through suitable tubes into the space between these two walls I and l.

According to the new construction the inner wall I of the hollow core is bent inwardly at two places opposite to each other so as to form two ribs whose cross-sectional area is gradually reduced towards the rear. These ribs produce in the severed plug 3 of the passing strand grooves 4 through which the admission of air from without to the space between the two walls I and I is constantly ensured so that the severing of the plug occurs at the intended place, that is to say, at the outlet end of the hollow core I by the action of the atmospheric air which is drawn in. In this case the aforementioned disadvantage, that is to say, the cutting of the strand of clay is avoided.

I claim as my invention:

A mouthpiece for strand presses for the manufacture of closed hollow bricks from plastic materials, the casing of the hollow core of the extrusion press mouthpiece being formed by a double wall, the inner wall of which consists of corrugated sheet iron and is provided at two opposite places with ribs for producing grooves in the plugs of the strand extending to the place of severance of them.

JAN PUTTERLfK. 

